Analog computer system for solving inequalities

摘要

1,045,778. Electric analogue calculating. CSF-COMPAGNIE GENERALE DE TELEGRAPHIE SANS FIL and SOC. MAROCAINE DE RECHERCHES, D'ETUDES ET DE DEVELOPPEMENTS " SOMAREDE." April 23, 1964 [April 26, 1963], No. 16967/64. Heading G4G. An arrangement, Fig. 1, for solving a system of equations and inequalities such as: comprises: generators G1 ... Gq producing outputs proportional to the unknown x1 . xq; error calculating means C receiving the generator outputs, and developing error signals f1...fp and g1 . . . gp; and a switch unit R receiving the error signals and producing control signals for the generators G1 ... Gq, the g error signals being coupled through an intermediate device I, which puts into operation circuits corresponding to g = 0 when x1... xq tend to make g0 and disconnect these circuits in the opposite case. The device I comprises an integrator or amplifier S, Fig. 2, having a switch D in its input and its output connected to the switch unit R. Switch D is controlled by a sign detector DS fed by a subtractor CS which delivers an output g-#. If g is greater than zero, switch D is in position 2 shorting out integrator S so that DS is controlled only by signal g, and the switch D will remain in its 2 position. If g goes negative, switch D changes to its 1 position and circuit S provides an output # whose effect is to modify the control voltages of generators G1 ... Gq so as to maintain g = 0. DS is then controlled by a signal -#. In a modification of the unit I, Fig. 5 (not shown), a second switch ganged with switch D disconnects integrator S from unit R in the position 2 and connects an earth potential to.unit R. An alternate form of unit I, Fig. 6 (not shown), employs diode switches D1, D2 suitably biased to provide the necessary switching operation.